Radio-Frequency Identification (RFID) technology has become widely used in a large number of industries including, for example, transportation, manufacturing, waste management, postal tracking, airline baggage reconciliation, and highway toll management. A typical RFID system includes RFID tags, an RFID reader having an antenna, and a computing device. The RFID reader typically includes a transmitter that may provide energy or information to the tags, and a receiver to receive identity and other information from the tags. The computing device processes the information obtained by the RFID reader.
The transmitter outputs radio-frequency (RF) signals through the antenna to create an electromagnetic field that enables the tags to return an RF signal carrying the information. In some configurations, the transmitter initiates communication, and makes use of an amplifier to drive the antenna with a modulated output signal to communicate with the RFID tag. In other configurations, the RFID tag receives a continuous wave signal from the RFID reader and initiates communication by responding immediately with its information.
RFID tags may be active or passive. Active RFID tags include an internal power source, while passive RFID tags use RF energy received from the transmitter to power the RFID tag. In either case, the RFID tags communicate with the RFID reader using a pre-defined protocol, allowing the RFID reader to receive information from one or more tags. The computing device serves as an information management system by receiving the information from the RFID reader, and performing some action, such as updating a database or sounding an alarm. In addition, the computing device serves as a mechanism for programming data into the tags via the transmitter.
Typically, information received from RFID tags is specific to a particular application, but often provides identification for an article to which the tag is fixed such as a manufactured article, a vehicle, an animal or individual, or virtually any other tangible article. In various industries such as, for example, the commercial and civil aviation industries, there are various government mandated requirements concerning flame-resistance of materials used in that industry.